How useful is the traditional panacea of re-installing macOS in Big Sur? And is it worth maintaining an external recovery disk to deal with problems?
Older versions of Catalina can fail to erase the System and Data volumes, but 10.15.6 should be able to, making clean re-installation simpler.
Follow Apple’s instructions for a clean re-install, and you’ll probably hit an error, and be left floundering in Recovery mode with an unbootable system.
When you go to perform a clean re-install of Catalina, what should you do? Which volume(s) to erase or delete, and how to fix problems?
Should you install, re-install, or clean (re-)install macOS? Why, how to, and what they entail.